SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58d79e7fee4b451fe7218925d42d02d947ac58cf50c0006d0049078d4c5f73ae' 
  AND token = 'V2vOzBYGpDrKnagtas3FF15JLtMrro7n1jGrPafbaa4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}